Neurology Risk score Strong evidence Clinical review pending v1.0.0

Glasgow Coma Scale (GCS)

What is the patient's level of consciousness?

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About this tool

Standardised assessment of eye, verbal and motor responses; supports 'not testable' components.

Intended use

Patients with impaired consciousness, especially after traumatic brain injury.

Outcome

Level of consciousness

Time horizon

Point in time

Derivation population

Developed for head-injured patients; used across acute care.

Limitations

Total score loses information — report components.
Confounded by intubation, sedation, eye swelling and aphasia.

Clinical problems

Head and neck trauma Acute stroke

Evidence

Evidence level

Strong evidence

Derived and externally validated in multiple cohorts (including prospective studies) and incorporated into major clinical guidelines. Methodology

Evidence summaries for this tool are awaiting independent clinical review. Statistics are shown only where they could be attributed to a specific publication.

References

Original publicationTeasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet 1974;2:81-84. Find on PubMed (opens in a new tab)
Review / updateTeasdale G, Maas A, Lecky F, et al. The Glasgow Coma Scale at 40 years: standing the test of time. Lancet Neurol 2014;13:844-854. Find on PubMed (opens in a new tab)

Version history

Version	Formula	Effective	Reviewer	Changes
v1.0.0	Teasdale & Jennett 1974 (2014 terminology)	2026-10-03	—	Initial implementation with reference test vectors.

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Strong evidence Point in time

Clinical decision support only. Interpret results in the context of the individual patient and current guidance; HumanPulse does not replace professional medical judgment.